Impact of male sterility and xenia on grain quality traits of maize

Abstract Cytoplasmic male sterility (cms) and xenia increase grain yield of maize in most cases, as shown here for three Swiss cms-hybrids. This combined effect is called Plus-Hybrid. It is of high interest to know if these factors change as well the competition for nitrogen and carbon. This was investigated for three cms-hybrids combined with six pollinator hybrids, including themselves, in small-plot trials in six environments in Switzerland in 1998 and 1999. Contents of grain nitrogen and carbon were similar and were not significantly influenced by cms. In contrast, xenia influenced the genotype-specific grain nitrogen content; the pollinator × genotype interaction was significant. The general pollinator ability for protein yield showed the same pattern as the one for grain yield. The results suggest that the protein yield can be enhanced, in parallel with grain yield, to an extent of 10% ( P